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Spring MVC Integration

Grails uses Spring MVC as the underlying web application framework. Spring MVC might not be the simplest framework to use but it is most definitely one of the most extensible making it perfect for Grails. The Grails servlet extends Spring's DispatcherServlet to bootstrap the Grails environment, there is then a single Spring MVC controller called org.codehaus.groovy.grails.web.servlet.mvc.SimpleGrailsController that handles all Grails controller requests.